Page:The Gall Wasp Genus Cynips.pdf/256

 have done extensive field work in that portion of the country. Young galls of fulvicollis appear in June or July, earlier further south (June 6, 1927, in southeastern Kansas). Fully grown galls occur among the June collections from Kansas and in an August 25 collection from Roselle, New Jersey. The galls are deciduous, falling to the ground in September or October, by which time they contain some pupae. Adults are to be found in the galls in October of the year in which emergence occurs, but the insects do not chew out before the middle of November. Most of the emergence occurs before the end of December, but thruout the rest of the winter and early spring the insects continue to come out of the galls on bright days, especially if these have been immediately preceded by very low temperatures. The subapterous adults have been taken on several occasions running over the snow.

The most southwestern variety, vorisi, completes most of its emergence in the first winter after the development of the gall, thus holding to the life-history typical for the rest of the genus Cynips. On the other hand, some of the individuals of vorisi, and most of the insects of canadensis, fulvicollis, major, and gigas remain until a second or even a third winter in the galls before transforming into adults. Weld and Brodie first noted this, and my own experience confirms it. While only the northeastern varieties of fulvicollis were known, this two-year emergence seemed so exceptional as to suggest the exclusion of the species from the genus Cynips. The discovery of the shorter life cycle in our variety vorisi indicates how a physiologic quality that is ordinarily of generic rank may be modified by environmental factors. The small amount of first-year emergence which our records show for the more northern varieties may come from second-year galls that were indiscriminately included with first-year specimens in our collections.

On circumstantial evidence, we are now considering the long-winged pallipes the bisexual form of one of the shortwinged agamic forms of fulvicollis. The data for this conclusion are detailed under pallipes. This bisexual insect is close to the bisexual forms known in the subgenus Acraspis, occurring in a seed-like bud gall very much resembling a bisexual Acraspis gall. The most distinctive thing in the bisexual Philonix is its unusual wing-body ratio of 1.17